Savitzky and Golay Smoothing Filters
Lispix implementation: s&g-coefs (nl nr m deriv)
- nl - number of neighbors to left.
- In practise, use lots of neighbors, up to about the width of the peaks
- Full width of degree 4 filter should be between 1x and 2x FWHM of features
- nr - number of neighbors to right
- (Points averaged = nl + nr + 1).
- nl + nr >= m.
- m - order of smoothing poynomial.
- Usual values are 2, or 4 for quadratic or quartic.
- 0 is for simple averaging.
- deriv, deriv <= m (m usually >= 4.)
In the Filter / variable buttons, nl = radius, nr = radius.